If a penetration tester was able to access the organization's wireless network from outside of the building using Aircrack-ng, then it means that the wireless network was not secured with strong encryption or authentication methods. Aircrack-ng is a tool that can crack weak wireless encryption schemes such as WEP or WPA-PSK using various techniques such as packet capture, injection, replay, and brute force. To remediate this issue, the client should change to Wi-Fi equipment that supports strong encryption such as WPA2 or WPA3, which are more resistant to cracking attacks. Using directional antennae may reduce the signal range of the wireless network, but it would not prevent an attacker who is within range from cracking the encryption. Using WEP encryption is not a good recommendation, as WEP is known to be insecure and vulnerable to Aircrack-ng attacks. Disabling Wi-Fi may eliminate the risk of wireless attacks, but it would also eliminate the benefits of wireless connectivity for the organization.